Refactor the index AM API slightly: move currentItemData and

currentMarkData from IndexScanDesc to the opaque structs for the
AMs that need this information (currently gist and hash).

Patch from Heikki Linnakangas, fixes by Neil Conway.

2 files changed, 18 insertions, 17 deletions

diff --git a/src/backend/access/gist/gistget.c b/src/backend/access/gist/gistget.c
index f36653babdf..f1d2c777c2f 100644
--- a/src/backend/access/gist/gistget.c
+++ b/src/backend/access/gist/gistget.c
@@ -8,7 +8,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/access/gist/gistget.c,v 1.63 2007/01/05 22:19:22 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/access/gist/gistget.c,v 1.64 2007/01/20 18:43:35 neilc Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -106,8 +106,8 @@ gistgettuple(PG_FUNCTION_ARGS)
 	 * If we have produced an index tuple in the past and the executor has
 	 * informed us we need to mark it as "killed", do so now.
 	 */
-	if (scan->kill_prior_tuple && ItemPointerIsValid(&(scan->currentItemData)))
-		killtuple(scan->indexRelation, so, &(scan->currentItemData));
+	if (scan->kill_prior_tuple && ItemPointerIsValid(&(so->curpos)))
+		killtuple(scan->indexRelation, so, &(so->curpos));
 
 	/*
 	 * Get the next tuple that matches the search key. If asked to skip killed
@@ -138,7 +138,8 @@ gistgetmulti(PG_FUNCTION_ARGS)
  * tuples. Returns true iff a matching tuple was found.
  */
 static int
-gistnext(IndexScanDesc scan, ScanDirection dir, ItemPointer tids, int maxtids, bool ignore_killed_tuples)
+gistnext(IndexScanDesc scan, ScanDirection dir, ItemPointer tids,
+		 int maxtids, bool ignore_killed_tuples)
 {
 	Page		p;
 	OffsetNumber n;
@@ -151,7 +152,7 @@ gistnext(IndexScanDesc scan, ScanDirection dir, ItemPointer tids, int maxtids, b
 
 	so = (GISTScanOpaque) scan->opaque;
 
-	if (ItemPointerIsValid(&scan->currentItemData) == false)
+	if (ItemPointerIsValid(&so->curpos) == false)
 	{
 		/* Being asked to fetch the first entry, so start at the root */
 		Assert(so->curbuf == InvalidBuffer);
@@ -226,7 +227,7 @@ gistnext(IndexScanDesc scan, ScanDirection dir, ItemPointer tids, int maxtids, b
 		}
 
 		if (!GistPageIsLeaf(p) || resetoffset ||
-			!ItemPointerIsValid(&scan->currentItemData))
+			!ItemPointerIsValid(&so->curpos))
 		{
 			if (ScanDirectionIsBackward(dir))
 				n = PageGetMaxOffsetNumber(p);
@@ -235,7 +236,7 @@ gistnext(IndexScanDesc scan, ScanDirection dir, ItemPointer tids, int maxtids, b
 		}
 		else
 		{
-			n = ItemPointerGetOffsetNumber(&(scan->currentItemData));
+			n = ItemPointerGetOffsetNumber(&(so->curpos));
 
 			if (ScanDirectionIsBackward(dir))
 				n = OffsetNumberPrev(n);
@@ -285,7 +286,7 @@ gistnext(IndexScanDesc scan, ScanDirection dir, ItemPointer tids, int maxtids, b
 				 * we can efficiently resume the index scan later.
 				 */
 
-				ItemPointerSet(&(scan->currentItemData),
+				ItemPointerSet(&(so->curpos),
 							   BufferGetBlockNumber(so->curbuf), n);
 
 				if (!(ignore_killed_tuples && ItemIdDeleted(PageGetItemId(p, n))))
diff --git a/src/backend/access/gist/gistscan.c b/src/backend/access/gist/gistscan.c
index 08ca73357c0..a275bb257ce 100644
--- a/src/backend/access/gist/gistscan.c
+++ b/src/backend/access/gist/gistscan.c
@@ -8,7 +8,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/access/gist/gistscan.c,v 1.66 2007/01/05 22:19:22 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/access/gist/gistscan.c,v 1.67 2007/01/20 18:43:35 neilc Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -42,12 +42,6 @@ gistrescan(PG_FUNCTION_ARGS)
 	GISTScanOpaque so;
 	int			i;
 
-	/*
-	 * Clear all the pointers.
-	 */
-	ItemPointerSetInvalid(&scan->currentItemData);
-	ItemPointerSetInvalid(&scan->currentMarkData);
-
 	so = (GISTScanOpaque) scan->opaque;
 	if (so != NULL)
 	{
@@ -82,6 +76,12 @@ gistrescan(PG_FUNCTION_ARGS)
 		scan->opaque = so;
 	}
 
+	/*
+	 * Clear all the pointers.
+	 */
+	ItemPointerSetInvalid(&so->curpos);
+	ItemPointerSetInvalid(&so->markpos);
+
 	/* Update scan key, if a new one is given */
 	if (key && scan->numberOfKeys > 0)
 	{
@@ -111,8 +111,8 @@ gistmarkpos(PG_FUNCTION_ARGS)
 			   *n,
 			   *tmp;
 
-	scan->currentMarkData = scan->currentItemData;
 	so = (GISTScanOpaque) scan->opaque;
+	so->markpos = so->curpos;
 	if (so->flags & GS_CURBEFORE)
 		so->flags |= GS_MRKBEFORE;
 	else
@@ -160,8 +160,8 @@ gistrestrpos(PG_FUNCTION_ARGS)
 			   *n,
 			   *tmp;
 
-	scan->currentItemData = scan->currentMarkData;
 	so = (GISTScanOpaque) scan->opaque;
+	so->curpos = so->markpos;
 	if (so->flags & GS_MRKBEFORE)
 		so->flags |= GS_CURBEFORE;
 	else